1. Field of the Invention
The invention relates to the field of magnetically guided medical devices, specifically a medical device deployed to move freely within the lumens, cavities and chambers of the human body according the computer aided control of a physician.
2. Description of the Prior Art
Ingestible diagnostic, delivery and therapeutic devices, such as the ‘GI capsules’, which travel through the cavities and ducts of the gastrointestinal tract, has been in use for over a decade. When a patient swallows just such a device which commonly takes the shape of a pill or capsule, the natural muscular (peristaltic) wave of the digestive tract propels it through the intestinal lumen. While the capsule is moving through the GI tract, a small camera disposed within the capsule enables the physician to inspect the walls of the intestinal ducts for possible detection of tumors, ulcers, and/or bleeding. However, the speed, position, and the direction of the capsule and by therefore by extension the small camera contained within it, are uncontrolled. Currently, obtaining and maintaining a desired observational point or viewing direction is impractical and most of the intestinal walls remain uninspected during a single pass, requiring additional capsules to be swallowed which increase the expense and time used to complete the procedure. Additionally, delivering drugs to a specific locale within the GI tract using a swallowed robotic capsule is imprecise and mostly unattainable.
Other methods for examining and delivering therapeutic drugs to the GI tract include manually operated devices common to endoscopy and colonoscopy. These methods have limited success in reaching clinically important anatomic sites and are generally not comfortable to the patient's experience. Additionally, therapeutic drug delivery to organs such as the brain, the heart, the kidneys, and other critical areas has similar difficulties in accessibility for the purposes of diagnosis and therapeutic treatment.
With the rapid increase of cases such as stomach ulcers and colon cancers, effective and painless methods of regular preventive and anticipatory examinations are desired. Specifically, what is needed is an apparatus and method that allows a small magnetic capsule that is orally ingested to be carefully controlled and guided as it traverses the GI tract of a patient with a minimum level of patient discomfort. The apparatus should also include means for examining specific portions the patient's GI tract as well as delivering a therapeutic or medicating agent to that specific portion by remote command of an operating physician.
There is a considerable library of prior patents wherein attempts have been made to control the movement of an untethered capsule through the body lumens. The prior art suffers from the fundamental inability of controlling an untethered device while being suspended in a levitating state. The inherent instability of an untethered device is known to those familiar with the art of guiding and controlling a permanent magnet in three dimensional space with six degrees of freedom, a condition described by the formal description of Earnshaw exclusion principle.
The presentation and the disclosed solutions provided by the prior art fail to address the fact that a medical device such as an endoscopic capsule with a specific mass necessitate a magnetic force and force gradient sufficient to lift, levitate, rotate and translate such an object in a suspended state. The prior art provides for literal descriptions of such alleged physical control, but do not disclose any solution that practically enables such control. This failure to enable a solution to the problem renders such prior art embodiments impractical and unusable.
Because of these drawbacks, what is needed is further development of the method and system of the described embodiments in Shachar, “Apparatus And Method For Catheter Guidance Control And Imaging”, U.S. Pat. No. 7,769,427, which discloses a magnetically guided tethered catheter to provide a system for magnetic guidance control and imaging using a magnetic field and field gradient to rotate, translate and levitate a medical untethered-capsule.
Recently, magnetic systems have been disclosed wherein magnetic fields produced by one or more electromagnets are used to guide and advance a magnetically-tipped device. The electromagnets in such systems produce large magnetic fields that are potentially dangerous to medical personnel and that can be disruptive to other equipment. A novel solution to the limitations noted by the art was developed by the introduction of a magnetic guidance system titled “Catheter Guidance Control and Imaging apparatus (CGCI)”, by Magnetecs corp. of Inglewood California. The properties and embodiments of the “CGCI” apparatus and methods are detailed by the following patents and applications: U.S. Pat. No. 7,769,427, Apparatus and Method for Catheter Guidance Control and Imaging; 2006/0116634, System and Method for Controlling Movement of a Surgical Tool; 2006/0114088, Apparatus and Method for Generating a Magnetic Field; 2006/0116633, System and Method for a Magnetic Catheter Tip; U.S. Pat. No. 7,280,863, System and Method for Radar-Assisted Catheter Guidance and Control; 2008/0027313, System and Method for Radar-Assisted Catheter Guidance and Control; 2007/0016006, Apparatus and Method for Shaped Magnetic Field Control for Catheter, Guidance, Control, and Imaging; 2007/0197891, Apparatus for Magnetically Deployable Catheter with Mosfet Sensor and Method for Mapping and Ablation; 2009/0248014, Apparatus for Magnetically Deployable Catheter with Mosfet Sensor and Method for Mapping and Ablation; 2008/0249395, Method And Apparatus for Controlling Catheter Positioning and Orientation; Ser. No. 12/103,518, Magnetic Linear Actuator for Deployable Catheter Tools; 2009/0253985, Apparatus and Method for Lorentz-Active Sheath Display and Control of Surgical Tools; 2009/0275828, Method and Apparatus for Creating a High Resolution Map of the Electrical and Mechanical Properties of the Heart; 2010/0130854, System and Method for a Catheter Impedance Seeking Device; Ser. No. 12/475,370, Method and Apparatus for Magnetic Waveguide Forming a Shaped Field Employing a Magnetic Aperture for Guiding and Controlling a Medical Device; Ser. No. 12/582,588, Method for Acquiring High Density Mapping Data With a Catheter Guidance System; Ser. No. 12/582,621, Method for Simulating a Catheter Guidance System for Control, Development and Training Applications; Ser. No. 12/615,176, Method for Targeting Catheter Electrodes; Ser. No. 12/707,085, System and Method for Using Tissue Contact Information in the Automated Mapping of Coronary Chambers Employing Magnetically Shaped Fields; PCT/US2009/064439, System and Method for a Catheter Impedance Seeking Device; PCT/US2010/036149, Method and Apparatus for Magnetic Waveguide Forming a Shaped Field Employing a Magnetic Aperture for Guiding and Controlling a Medical Device; PCT/US2010/052696, Method for Acquiring High Density Mapping Data With a Catheter Guidance System; and PCT/US2010/052684, Method for Simulating a Catheter Guidance System for Control, Development and Training Applications. Each of the above listed patents and applications for patent are incorporated in their entirety by reference herein.
Nevertheless, there is a great and still unsatisfied need for an apparatus and method for guiding, steering, and advancing invasive devices and for accurately controlling their positions for providing positioning of magnetic fields and field gradient, for providing a fields configured to push/pull, bend/rotate, and by further enabling apparatus to align the capsule to achieve controlled movement in three dimensional space.